Soils are a prominent feature of floodplain environments, and we include them in this section because most of the available information on ancient soils pertains to alluvial examples, aside from those in Quaternary-Recent time.
A deposition of sediment over a long period of time by a river; an alluvial layer
Pertaining to or composed of alluvium, or deposited by a stream or running water Relating to, composed of, or found in alluvium, which is unconsolidated, poorly sorted, detrital sediments ranging from clay to gravel sizes and characteristically fluvial in origin
Sedimentary material from running water, sometimes containing precious metals, which is deposited in river beds, flood plains, lakes or at the foot of mountain slopes
An adjective referring to soil or earth material which has been deposited by running water, as in a riverbed, flood plain, or delta
Referring to deposits resulting from natural river activity, including sediments laid down in river beds, flood plains, lakes, fans at the foot of mountain slopes and estuaries
Soil that contains clay, silt, sand or gravel deposited by running water is said to be alluvial Grapes grown in mostly sandy and stony alluvial soil produce wines with more concentrated fruit flavors
Pertaining to material carried or laid down by running water Alluvium is the material deposited by streams It includes gravel, sand, silt, and clay
Material transported and deposited by the action of flowing water, such as clay, silt sand and gravel
An adjective referring to alluvium, which are sediments deposited by erosional processes, usually by streams
Having stream deposits and sediments formed by the action of running water (California Coastal Commission 1987)
Pertaining to, contained in, or composed of, alluvium; relating to the deposits made by flowing water; washed away from one place and deposited in another; as, alluvial soil, mud, accumulations, deposits
Alluvial soils are soils which consist of earth and sand left behind on land which has been flooded or where a river once flowed. made of soil left by rivers, lakes, floods etc
Material deposited by rivers. It consists of silt, sand, clay, and gravel, as well as much organic matter. Alluvial deposits are usually most extensive in the lower part of a river's course, forming floodplains and deltas, but they may form at any point where the river overflows its banks or where the flow of a river is checked. They yield very fertile soils, such as those of the deltas of the Mississippi, Nile, Ganges and Brahmaputra, and Huang (Yellow) rivers. They contain most of the world's supply of tin ore, as well as, in some regions, gold, platinum, and gemstones
A fan-shaped sediment deposit formed by a stream that flows from a steep mountain valley or gorge onto a plain or the junction of a tributary stream with the main stream Alluvial fans contain active stream channels and boulder bars, and recently abandoned channels Alluvial fans are predominantly formed by alluvial deposits and are modified by infrequent sheetflood, channel avulsions and other stream processes They may also be subject to debris flow and debris torrents
Used to describe the fanning aspect of a stream as it leaves a mountain to disperse in a valley; also used in desert areas to describe the effects of a mineral breaking off the steep sides of mountains and being spread by later effects of water or wind
A low, outspread mass of loose materials and/or rock material, commonly with gentle slopes, shaped like an open fan or a segment of a cone, deposited by a stream (best expressed in semiarid regions) at the place where it issues from a narrow mountain or upland valley; or where a tributary stream is near or at its junction with the main stream It is steepest near its apex which points upstream and slopes gently and convexly outward (downstream) with a gradual decrease in gradient GG
A fan-shaped deposit of unconsolidated material and debris, forming at the point where a stream emerges from a narrow valley onto a broader, less sloping valley floor
A low, outspread, relatively flat to gently sloping mass of loose rock material, shaped like an open fan or a segment of a cone, deposited by a stream (esp in a semiarid region) at the place where it issues from a valley upon a plain or broad valley, or where a tributary stream is near or at its junction with the main stream, or wherever a constriction in a valley abruptly ceases or the gradient of the stream suddenly decreases; it is steepest near the mouth of the valley where its apex points upstream, and it slopes gently and convexly outward with gradually decreasing gradient
A low, outspread, relatively flat to gently sloping mass of loose rock material deposited by a stream where it flows from a narrow mountain valley onto a plain or broad valley
A sloping fan-shaped accumulation of sediment found where a stream leaves a narrow valley and spreads out over a broad geographic area Most frequently found in arid areas
a fan-shaped deposit of gravel, sand and silt dropped by a stream where there is a decrease in slope e g from mountains onto a level plain or into a lake or stream
Usually seen at a junction where a small stream joins a larger one or at the point where water flows through a narrow gorge that opens onto a plain, this fan-shaped deposit of soil is left behind
A fan-shaped deposit of generally coarse material created where a stream flows out onto a gentle plain; a geomorphologic feature characterized by a cone or fan-shaped deposit of clay, silt, sand, gravel, and boulders that have been eroded from mountain slopes, transported by flood flows, and deposited on the valley floor ADVANCE \x 540